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FINAL ADJUSTMENTS
The two aileron pushrods should be adjusted so that with no control input, the rear-
most balls on the bell cranks are positioned directly over the pivot point for the
transverse lever. This will place the horizontal arms on these bell cranks parallel with the
collective levers. Since these pushrods attach to the servo at an angle from either side,
in order to achieve equal movement on the aileron control, the balls on the aileron servo
arm should have been offset forward, per the drawings.
Now its time to adjust the elevator control system. The pushrod-to-servo adjustment
should be accomplished with the same procedure we used on the collective servo.
When positioning the servo arm on the elevator servo, it should be placed on a spline so
that when the servo is in neutral, the upper elevator bell cranks balls (the unused ones at
this time) are vertical. This will determine the elevator trim. The two pushrods should
then be attached to the rear of this top bell crank, and back to the elevator lever. Each of
these pairs of pushrods should be of equal length (two different lengths, but two
matched pairs). Once these are adjusted to equal length, they should NEVER be
adjusted further.
These are not the linkages to use to mechanically trim the helicopter. If they are not
of equal length, binding will occur at some point in their movement.
One thing to keep in mind here, these two sets of pushrods are NOT
ADJUSTED except to make them equal. The servo arm on the elevator must be
positioned on a spline that will allow the final elevator lever to be parallel to the
main shaft.
Now it is time to adjust the four pushrods that support the swash plate. All four of
these pushrods should be of identical length. These pushrods should be adjusted so as
to give your swash plate equal movement up and down, as the collective lever is moved
to each extreme. If your Intrepid needs any trim adjustments that cannot be
accomplished from the transmitter, these are the pushrods that should be adjusted.
The pushrods that attach the hiller levers (flybar control arms) to the washout levers
should, of course, be of identical length. A “generic” length was given before, and it will
work well. If you are going to maximize every control on your Intrepid for 3D style
aerobatics, you can also shorten these two pushrods slightly (they MUST remain equal
in length). This will allow the washout levers to be slightly higher throughout the
collective range, and allow a small increase in cyclic travel at extreme positive collective.
Now, it’s on the one of the most crucial adjustments on your helicopter, although it’s
one of the easiest to achieve correctly. The bell-hiller mixers that are attached to the
blade holders should be perfectly horizontal in the center of your collective range. If this
is adjusted correctly, your Intrepid will always have the same “feel” when flying, no
matter where the collective is. The bell pushrods (they go from the swash plate to the
bell-hiller mixer), and the hiller pushrods (the short ones from the flybar seesaw to the
mixing arm), should be adjusted so that at “neutral” collective the bell-hiller mixer is
exactly horizontal. What this means is that if you want to have a total pitch range of plus
10 degrees to minus 10 degrees, the bell-hiller mixers should be horizontal at 0 degrees
pitch. If you are a beginner, these mixers should be horizontal at a pitch setting of +5
degrees, with ten degrees being maximum pitch and o degrees being minimum pitch.
